Electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles use power devices such as IGBTs (insulated-gate bipolar transistors) and power MOSFETs (metal-oxide-semiconductor field-effect transistors) to drive a motor in the powertrain and in applications such as charging units and power conversion units. Over time, as power devices age, electrical parameters such as a threshold voltage and on resistance can change. The changes in these electrical parameters may degrade vehicle performance. Further, replacing the power devices is expensive and may require the inconvenience of taking the vehicle to a service station. It is a problem to detect aging power devices and adjust parameters of the power devices.